Tape creasing apparatus



March 22, 1960 2. w. ARMSTRONG I TAPE CREASING APPARATUS 2 Sheets-Sheet1 Filed Aug. 4, 1959 INVENTOR ATTORNEYS March 22', 1960 2. w. ARMSTRONG2,929,303

TAPE CREASING APPARATUS Filed Aug. 4, 1959 2 Sheets-Sheet 2 IN VENTOR BYyw @PM ATTORNEYS United States. Patent This invention relates to animproved apparatus for longitudinally creasing the sheetrock tape usedto cover I corner joints between wall boards in the so-called dry wallconstruction.

In making corner joints between two gypsum-board sheets it is customaryto apply cement to the sheets adjacent the joint and to manuallylongitudinally fold the perforated binding tape, to insert the tape intothe corner joint, and to cement the tape on both sides of the angle atthe same time. It has proven to be time consuming and difiicult for thefinisher to manually crease the tape about its central longitudinal axisand consequently various types of tape creasing devices have beendeveloped for use in the trade.

The primary object of the present invention is to provide an improvedtape creasing apparatus of sturdy compact construction and especiallydesigned to prevent clogging and jamming of the tape as it is drawnthrough the creasing means.

A more specific object of the present invention is to provide a tapecreasing apparatus which will automatically crease the tape about itscentral longitudinal axis .as the tape is drawn from a supply rollbetween two elements which are resiliently biased together, one of saidelements being a guide block having two angularly converging grooves inone surface thereof and the other of said elements being a cover memberpivotally connected at one edge to said guide block for contiguousengagement with the adjacent surface of the guide block.

Other objects and advantages of my invention will become more apparentfrom a study of the following specification when considered inconjunction with the accompanying drawings in which:

Fig. 1 is a perspective view of the tape creasing apparatus with thetape being fed through the creasing means;

Fig. 2 is a perspective view of the apparatus with the tape being fed ina fiat condition through the guide means.

Fig. 3 is a plan view of the apparatus with the cover pivoted to itsopen position and with the tape removed;

Fig. 4 is an elevational view of the apparatus with the cover in itsclosed and locked position; and

Figs. 5 and 6 are sectional views taken along lines 5-5 and 66 of Fig.4.

Referring now to the drawings, and more particularly first to Figs. 3and 4, the tape creasing apparatus con sists of a guide block 1 havingan inclined upper surface as shown in Fig. 4. Pivotally connected to theguide block 1 by means of hinges 2 is the cover element 3 which isadapted to be swung from an open position (Fig. 3) to a closed position(Fig. 4) extending over the upper surface of the guide block with thelower surface 3a of the cover in contiguous engagement with the uppersurface 1a of the guide block.

Secured to the sides of the guide block 1 at the rear end thereof bymeans of screws 4 is the metal U-shaped bracket 5. Each of the legs 5a,5b of the U-shaped bracket contains oppositely arranged grooves 6between 2,929,303 Patented- Mar. 22 1960 Fee.

2 which is transversely and removably mounted the spindle 7 of the tapesupporting roller 8.

In the upper surface 1a of guide block 1 are two angularly inclinedgrooves 9 and 10 which form an inverted V-shaped slot in the guideblock. As shown in Figs.- 3-6, the angle between the grooves 9 and 10progressively diminishes from approximately at the rear of the guideblock to approximately 0 at the front thereof.

Rotatably connected to the rear end surface 1b .of the guide block 1 isthe guide roller 11. This guide roller 11 is parallel to and spaced fromthe end surface 1b and is rotatably mounted on the transverse portion ofthe U-shaped rod 12.

The tape creasing operation of the apparatus may now be readilydescribed. 7 i

The tape supporting roller 8 is lifted upwardly until the ends ofspindle 7 are removed from slots 6 in the U-shaped bracket 5 and thetape roll 13 is mounted on the tape supporting roller whereupon the endsof the spindle 7 are reinserted into the grooves 6 as shown in Fig. l.

With the cover 3 in the open position of Fig. 3 the free end 14 of thetape is fed into the grooves 9 and 10 in the upper surface of the guideblock. During this initial insertion of the tape into the guide block itmay be found to be desirable to manually crease the central longitudinalportion of the tape so that the tape will properly fit into the grooves.The tape will initially enter the guide block 1 at its end surface 1b ina substantially flat state and will be emitted from the front surface 10of the guide block in a longitudinally creased state with the edges ofthe tape brought together and the tape folded down the middle as shownin Fig. 1. The cover 3 is then pivoted about hinges 2 to its closedposition of Fig. 4 and is resiliently locked in this position byconnecting the free end of spring 15 to the locking pin 16 on guideblock 1, the other end of spring 15 being permanently connected to thecover 3.

The tape 14 is then drawn through the creasing apparatus as shown inFig. 1 and is progressively longitudinally creased from its initial flatcondition to it! final creased condition. The tension spring 15 isselfadjusting and allows the tape to move smoothly through the guideblock 1 without any choking or jamming. It is to be noted that the flatunder surface 3a of the cover will engage the upper surface of thecreased portion of the tape and, due to the action of spring 15, willresiliently bias the folded halves of the tape downwardly into thegrooves 9 and 10. Since the depth of each groove is approximately equalto half the width of the tape, the tape will be automatically creasedabout its central longitudinal axis as it is drawn through the creasingmeans.

The creasing apparatus may be removably connected to the fiat upper topmember 17 of step ladder 18 by means of the spring 19. One end of thespring 19 is fixedly secured to the bottom surface of guide block 1 bymeans of eyelet 20 while the other end of the spring is removablyconnected to the pin 21 on the guide block. Thus to secure the tapecreasing apparatus to the ladder, the guide block 1 is placed on the topstep 17 and the spring 19 is brought beneath the step and secured undertension to the pin 21.

The user of the apparatus may then stand on the step ladder and withdrawa desired length of tape from the roll 13 through the creasing or guideblock 1 and then tear off the length of creased tape for application tothe wallto-wall or ceiling-to-wall right angled joint.

Should it be desired to withdraw the tape from the roll 13 in a flatstate for certain applications, such as in finishing a butt jointbetween two coplanar sheets, in! stead of feeding the tape through thegrooves 9, 10 in the guide block 1 the tape end 14 may be brought underthe guide roller :11 and between the roller 11 and the rear 'inayibemade in the apparatus describedwithont deviating from my invention asset forth in the following claims.

I'claim: 1; Apparatus for longitudinally creasing a strip .of flat tapecomprising a guide block having a fiat upper surface containing a pairof longitudinally-extending angula'rly-arranged grooves of equal depththerein, said grooves being arranged in transverse'cross-section of theblock in an invertedV-shaped configuration, said grooves forming at afirst end of the guide block an obtuse angle and progressivelyconverging to form an acute angle adjacent :the other end of the guideblock, a cover element above the guide block and having a flat lowersurface, and means resiliently biasing the cover element into engagementwith the guide block whereby the'ta'pe will be progressively formed froma substantially fiat condition to a longitudinally-creased state as itis'drawn through the guide block from the first end to the other endthereof.

2. Apparatus for longitudinally creasing flat tape as it is removed froma roll thereof comprising a guide block having a flat upper surface, a vU-shaped bracket rigidly connected at the extremities of the legsthereof to the sides. of said guide block and extending outwardly fromone end thereof, a tape supporting roller removably connected betweenthe legs of said bracket, a cover element pivotally connected at oneedge to one side edge of the upper surface of the guide block, saidcover element having a flat lower surface which contiguously engages theupper surface of the guide block when the cover element is pivoted to aclosed position over the guide block, and means resiliently biasing thecoverelement into engagement with the flat upper surface of the guideblock, said guide block having in the upper surface thereof a pair ofgrooves of uniform ldepth extending longitudinally of the guide blockand arranged in transverse cross-section of the block in an invertedV-shaped configuration, said grooves forming at the end of the guideblock adjacent the U-shaped bracket an abtuse angle and progressivelyconverging to form an actue angle adjacent theother end of the guideblock so that the tape will be progressively formed from a flatcondition to a longitudinallycreasedv state as it is fed from a roll oftape mounted on said tape supporting roller through the guide blockgrooves.

References Cited in the file of this patent UNITED STATES PATENTS

